As a simple rule, it may be concluded from the actual literature that the more sophisticated genital sex reassignment is planned, the more complications can be expected.

In the following, typical complications of single steps of the procedure will be explained.

In most centers, vaginectomy is performed during phalloplasty or metoidioplasty at least 6 weeks after breast reduction and hysterectomy. A recent study from London revealed that most complications intra- and postoperatively concerned bleeding, which appeared to be related to vaginal length [8]. The median intraoperative blood loss was 700 ml (range 100–3,000 ml), mean postoperative blood loss was 200 ml (range 20–1,490 ml), and 22 % of all patients needed blood transfusions. Postoperative complications included wound infection (12.3 %), wound bleeding (14.6 %), and vaginal hematoma/abscess formation (6.7 %). In 5 %, bladder or urethral perforations occurred during the procedure, which could all be closed primarily without further consequences. Four percent needed prolonged catheterization due to the development of temporary hypotonic bladder. While most authors prefer only a mucosal vaginectomy, in our hands a radical vaginectomy including the vaginal muscle wall is preferred. The risk of leaving mucosal islands behind with later abscess or fistula formation seems to be reduced by this more radical approach. On the other hand, care has to be taken to close properly the peritoneal cavity in case it has been opened inadvertently. During 270 radical vaginectomies, we observed three cases of severe intra-abdominal bleeding postoperatively which demanded transabdominal revision.

In general, it is helpful to resect as much as possible of the vagina during previous hysterectomy and ovariectomy in order to reduce the risk of bleeding complications during vaginectomy [8].

Modern metoidioplasty is intended to be a one-stage procedure with simultaneous lengthening and straightening of the hypertrophied clitoris, combined with urethroplasty to the tip of the clitoris, vaginectomy, and neoscrotum formation by implantation of two testicular prostheses. Urethral reconstruction seems to be the most difficult part of the procedure and is responsible for most of the possible complications. Hage et al. described a high rate of urethral fistula (37 %) and stenosis formation (35 %) in a large series of 70 patients [12]. Loss or dislocation of testicular prostheses also frequently occurred (80 %). Overall patients needed an average of 2.6 operations to complete genital reconstruction; 25 % of all patients later demanded phallic reconstruction by radial forearm flaps.

A recent publication on two different methods of metoidioplasty utilizing buccal mucosa and labia minora flaps for urethral formation in 207 patients reported significantly less urethral complications (8–20 %). Minor complications were noted in nearly 30 %. Nearly 90 % of patients were able to void in a standing position after completing the procedure. Twelve percent later demanded for complete phallic reconstruction [13].

In conclusion, metoidioplasty may be suited for F-t-M transsexuals who have no interest in penetrative sexual intercourse and who have developed significant clitoral hypertrophy after long-term testosterone application. Genital sensation is generally well preserved [3].

As previously mentioned, the most widely used free flap for penile and urethral reconstruction actually is the radial free forearm flap with more than 800 cases published until 2013. Even if modifications and flap designs differ between several author groups, complication rates seem to be quite similar in large centers [3, 9, 14]. Monstrey and coworkers reported a rate of 226 operative revisions due to complications after 316 phalloplasties by radial free forearm flaps, mostly due to urethral and prosthetic complications [9]. Ralph and coworkers reported a 34 % revision rate only for urethral complications after 115 free forearm phalloplasties, even if phalloplasty was performed as a multistage procedure [15]. In our personal experience after 270 phalloplasties using a free forearm flap, more than 60 % needed urethral revision surgery, and 37 % had to be reoperated due to prosthetic complications. Following a suggestion from Monstrey, the numerous complications after microsurgical phalloplasty can be divided in several subgroups: